Sandvik Coromant 7859260 Turning Insert DNMG433-PR 4415

Product Description

The SANDVIK COROMANT 7859260 is a DNMG-style indexable turning insert designed for external and internal turning operations on CNC lathes and turning centers. Carrying the ANSI designation DNMG433 and ISO code DNMG 15 04 12-PR 4415, this insert features a 55-degree diamond (rhombic) shape with a negative side clearance and a neutral hand orientation. The substrate is solid carbide with a CVD-applied multilayer coating of TiCN, Al2O3, and TiN, which delivers the wear resistance and toughness balance required for steel machining. The PR chip breaker geometry is optimized for roughing and medium machining passes. Four cutting edges are available per insert, reducing per-edge tooling cost on high-volume runs.

This insert is intended for machining steel as its primary workpiece material, with secondary suitability for cast iron. It fits applications where high wear resistance is needed alongside adequate toughness, such as rough turning of carbon steel, alloy steel, and gray or ductile cast iron. It is used by machinists and CNC operators in production shops, job shops, and maintenance machining environments. The T-Max P series insert holder system provides the toolholder interface for this insert style.

Key Features

• CVD multilayer coating: TiCN, Al2O3, and TiN for high wear resistance on steel and cast iron
• PR chip breaker geometry suited for roughing and medium machining operations
• 55-degree diamond insert shape with negative side clearance for stable, rigid cutting
• Four usable cutting edges per insert for extended tooling economy
• Inscribed circle of 0.5 inches (12.70 mm) and corner radius of 1.19 mm (0.0469 inches)
• Compatible with both clamp and screw insert-holding methods

Compatibility

Designed for use in toolholders accepting DNMG-style inserts within the SANDVIK COROMANT T-Max P series. Also fits any standard DNMG433 or ISO DNMG 15 04 12 compatible toolholder from other manufacturers that accepts this insert geometry and clamping method.

Installation Notes

Installation is performed by a machinist or CNC toolroom technician. Power down and deactivate the machine spindle before indexing or replacing any cutting insert. Use the appropriate torx or hex key to secure the clamp or screw per the toolholder manufacturer specification. Inspect the insert pocket and seating surface for chips or debris before seating the new insert to ensure proper contact and cutting-edge alignment.